'use strict';
'use ndb';
const i = 5;
const f = 10.3;
const s = 'Hello';
const b = true;

const person = {
    name: 'Marcus Aurelius',
    born: 121,
    city: 'Roma',
    position: 'emperor'
};

person.city = 'Odessa';

const cities = [ 'Athens', 'Roma', 'London', 'Beijing', 'Kiev', 'Riga' ];
debugger;
const p1 = cities.push( 'pushing' ); // return length arr = 7
const p2 = cities.pop(); // 'pushing'
const p3 = cities.unshift( 'unshifting' ); // return length arr = 7
const p4 = cities.shift(); // 'unshifting'

cities.push( 'Odessa' );
cities.unshift( 'New York' );

console.log( 'shift: ' + cities.shift() );
console.log( 'pop: ' + cities.pop() );

console.log( { i }, typeof i );
console.log( { s }, typeof s );
console.log( { b }, typeof b );
console.log( { f }, typeof f );

console.log( { person }, typeof person );
console.log( { isArray: Array.isArray( person ) } );

console.log( { cities }, typeof cities );
console.log( { isArray: Array.isArray( cities ) } );

console.log( { instanceofArray: cities instanceof Array } );
